In display devices for graphic design use or medical use, regular calibration (CAL) is performed to correct display characteristic deterioration.
FIG. 4 is a diagram illustrating a configuration of a display device according to a related art. A display device includes a display unit using a display panel such as a liquid crystal display (LCD) or a projector (PJ). A warning screen-rendering circuit causes a video signal input from a personal computer or a video to be displayed on the display unit without change when calibration is unnecessary. A timer circuit detects an operating time of the display device or the number of days that have elapsed since calibration was previously performed, and outputs a warning output instruction to the warning screen-rendering circuit when the operating time or the number of days that have elapsed exceeds a reference value. When the warning output instruction is input from the timer circuit, the warning screen-rendering circuit determines that display characteristics have deteriorated, and causes a warning screen to be displayed on the display unit. Thus, the display device displays the warning screen, and recommends calibration to a user.
Meanwhile, Patent Document 1 discloses an LCD device that displays a message representing that it is necessary to exchange a lamp to a user when deterioration in brightness of a backlight (hereinafter referred to as a “BL”) is detected. Further, Patent Document 2 displays an LCD display device that gives an instruction for exchanging a BL lamp to a user based on a comparison between a BL drive value at the beginning of use and a BL drive value after a certain period of time elapses.